School of Resources and Safety Engineering, Central South University, Changsha, Hunan, China.
PLoS One. 2019 Feb 25;14(2):e0212881. doi: 10.1371/journal.pone.0212881. eCollection 2019.
The accurate location of induced seismicity is a problem of major interest in the safety monitoring of underground mines. Complexities in the seismic velocity structure, particularly changes in velocity caused by the progression of mining excavations, can cause systematic event mislocations. To address this problem, we present a novel construction method for an arbitrary 3D velocity model and a targeted hypocenter determination method based on this velocity model in underground mining. The method constructs a velocity model from 3D geological objects that can accurately express the interfaces of geologic units. Based on this model, the block corresponding to the minimum difference between the observed arrival times and the theoretical arrival times computed by the Fast Marching Method is located. Finally, a relocation procedure is carried out within the targeted block by heuristic algorithms to improve the performance. The accuracy and efficiency of the proposed method are demonstrated by the source localization results of both synthetic data and on-site data from Dongguashan Copper Mine. The results show that our proposed method significantly improves the location accuracy compared with the widely used Simplex and Particle Swarm Optimization methods.
震源精确定位是地下矿山安全监测中一个非常重要的问题。地震波速结构的复杂性，特别是开采过程中速度的变化，会导致事件的系统定位错误。针对这个问题，我们提出了一种新的任意 3D 速度模型的构建方法和基于该速度模型的地下采矿目标震源定位方法。该方法从能够准确表示地质单元界面的 3D 地质目标构建速度模型。基于该模型，定位到观测到时与由快速行进法计算的理论到时之间差值最小的块。最后，在目标块内通过启发式算法进行重定位过程，以提高性能。通过对冬瓜山铜矿的合成数据和现场数据的源定位结果，验证了所提出方法的准确性和效率。结果表明，与广泛使用的 Simplex 和 Particle Swarm Optimization 方法相比，我们提出的方法显著提高了定位精度。
